Heterocyclic compound and organic light emitting device including the same

ABSTRACT

An organic light-emitting device includes a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer. The emission layer includes at least one heterocyclic compound of Formula 1. The heterocyclic compound may be a host or a delayed fluorescent dopant. The organic light-emitting device including the heterocyclic compound may have a low driving voltage, high efficiency, high luminance, and a long lifespan.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2017-0048532, filed on Apr. 14, 2017, in the KoreanIntellectual Property Office, the entire content of which isincorporated herein by reference.

BACKGROUND 1. Field

One or more aspects of one or more embodiments of the present disclosurerelate to a heterocyclic compound and an organic light-emitting deviceincluding the same.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices that producefull-color images, have wide viewing angles, high contrast ratios, shortresponse times, and excellent characteristics in terms of brightness,driving voltage, and response speed, compared to devices in thepertinent art.

An example of such organic light-emitting device may include a firstelectrode disposed (e.g., positioned) on a substrate, and a holetransport region, an emission layer, an electron transport region, and asecond electrode, which are sequentially disposed on the firstelectrode. Holes provided from the first electrode, for example, maymove toward the emission layer through the hole transport region, andelectrons provided from the second electrode, for example, may movetoward the emission layer through the electron transport region.Carriers, such as holes and electrons, may then recombine in theemission layer to produce excitons. These excitons transition from anexcited state to a ground state, thereby generating light.

SUMMARY

One or more aspects of one or more embodiments of the present disclosureare directed to a novel heterocyclic compound and an organiclight-emitting device including the same.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

An aspect of one or more embodiments of the present disclosure isdirected to a heterocyclic compound represented by Formula 1:

In Formulae 1, 2-1, 2-2, 3-1, and 3-2,

X₁ may be O or S,

Ar₁ and Ar₂ may each independently be a substituted or unsubstitutedC₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₂-C₆₀heterocyclic group,

a1 and a2 may each independently be an integer from 0 to 3,

R₁ and R₂ may each independently be a group represented by Formula 2-1,

R₃ may be a group represented by Formula 2-2,

b1 and b2 may each independently be 0 or 1,

a1, a2, b1, and b2 may satisfy a1+b1≥1 and a2+b1≤1,

A₁ to A₄ may each independently be a benzene group, a naphthalene group,a phenanthrene group, a fluoranthene group, a triphenylene group, apyrene group, a chrysene group, a pyridine group, a pyrimidine group, apyrazine group, a pyridazine group, or a tetrazine group,

A₅ to A₈ may each independently be a benzene group, a naphthalene group,a phenanthrene group, a fluoranthene group, a triphenylene group, apyrene group, a chrysene group, a pyridine group, a pyrimidine group, apyrazine group, a pyridazine group, or a tetrazine group,

Y₁ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀),S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉),

Y₂ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀),S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉),

Y₃ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀),S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉),

Y₄ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀),S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉),

Y₅ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀),S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉),

when Y₁ is O, a group represented by Formula 2-1 may be different from agroup represented by Formula 2-2,

R₁₁ to R₁₄ may each independently be a group represented by Formula 3-1,a group represented by Formula 3-2, hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a substituted or unsubstitutedC₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group,a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —S(═O)(Q₁), or —P(═O)(Q₁)(Q₂), two ormore R₁₁(s) may optionally be linked to form a substituted orunsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstitutedC₂-C₆₀ heterocyclic group, two or more R₁₂(s) may optionally be linkedto form a substituted or unsubstituted C₅-C₆₀ carbocyclic group or asubstituted or unsubstituted C₂-C₆₀ heterocyclic group, two or moreR₁₃(s) may optionally be linked to form a substituted or unsubstitutedC₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₂-C₆₀heterocyclic group, and two or more R₁₄(s) may optionally be linked toform a substituted or unsubstituted C₅-C₆₀ carbocyclic group, or asubstituted or unsubstituted C₂-C₆₀ heterocyclic group,

when Y₂ is a single bond, at least one of R₁₃ and R₁₄ may be a grouprepresented by Formula 3-1 or a group represented by Formula 3-2,

R₁₅ to R₂₀ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic,—S(═O)(Q₁), and —P(═O)(Q₁)(Q₂),

b11 to b18 may each independently be an integer from 1 to 8,

at least one substituent of the substituted C₅-C₆₀ carbocyclic group,the substituted C₂-C₆₀ heterocyclic group, the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀aryloxy group, the substituted C₆-C₆₀ arylthio group,the substituted C₁-C₆₀ heteroaryl group, the substituted monovalentnon-aromatic condensed polycyclic group, and the substituted monovalentnon-aromatic condensed heteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

where Q₁, Q₂, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may eachindependently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group, and

*indicates a binding site to a neighboring atom.

Another aspect of one or more embodiments of the present disclosure isdirected to an organic light-emitting device including: a firstelectrode; a second electrode facing the first electrode; and an organiclayer that is disposed between the first electrode and the secondelectrode and includes an emission layer, wherein the organic layerincludes at least one of the heterocyclic compounds described above.

BRIEF DESCRIPTION OF THE DRAWING

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the drawing, which is a schematic view of an organiclight-emitting device according to an embodiment.

DETAILED DESCRIPTION

Reference will now be made in more detail to embodiments, examples ofwhich are illustrated in the accompanying drawings, wherein likereference numerals refer to like elements throughout. In this regard,the present embodiments may have different forms and should not beconstrued as being limited to the descriptions set forth herein.Accordingly, the embodiments are merely described below, by referring tothe drawing, to explain aspects of the present description. As usedherein, the term “and/or” includes any and all combinations of one ormore of the associated listed items. Expressions such as “at least oneof,” “one of,” and “selected from,” when preceding a list of elements,modify the entire list of elements and do not modify the individualelements of the list. Further, the use of “may” when describingembodiments of the present invention refers to “one or more embodimentsof the present invention.”

A heterocyclic compound according to an embodiment is represented byFormula 1 below:

X₁ in Formula 1 may be O or S.

Ar₁ and Ar₂ in Formula 1 may each independently be a substituted orunsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstitutedC₂-C₆₀ heterocyclic group.

In one embodiment, Ar₁ and Ar₂ may each independently be selected from:

a benzene group, a naphthalene group, a pyridine group, a pyrazinegroup, a pyrimidine group, a pyridazine group, a triazine group, aquinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, and aquinazoline group; and

a benzene group, a naphthalene group, a pyridine group, a pyrazinegroup, a pyrimidine group, a pyridazine group, a triazine group, aquinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, and aquinazoline group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl, group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, Ar₁ and Ar₂ may each independently be asubstituted or unsubstituted aromatic C₆-C₃₀ carbocyclic group, or asubstituted or unsubstituted π electron-depleted nitrogen-containingC₂-C₃₀ heterocyclic group.

In one or more embodiments, Ar₁ and Ar₂ may each independently beselected from:

a benzene group, a pyridine group, a pyrazine group, a pyrimidine group,a pyridazine group, and a triazine group; and

a benzene group, a pyridine group, a pyrazine group, a pyrimidine group,a pyridazine group, and a triazine group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group,a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group,a phenyl group substituted with a C₁-C₁₀ alkyl group, a phenyl groupsubstituted with —F, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a pyridinyl group, a pyrimidyl group, atriazinyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), and—N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one embodiment, Ar₁ and Ar₂ may each independently be a benzene groupor a pyridine group.

In one embodiment, Ar₁ and Ar₂ may each be a benzene group, butembodiments of the present disclosure are not limited thereto.

In Formula 1, a1 and a2 may each independently be an integer from 0 to3, b1 and b2 may each independently be 0 or 1, and a1, a2, b1, and b2may satisfy a1+b1≥1 and a2+b2≥1.

In one embodiment, a1 and a2 may each independently be 0 or 1, butembodiments of the present disclosure are not limited thereto.

In one embodiment, a1, a2, b1, and b2 may satisfy a1+b1=1 and a2+b2=1.

In one embodiment, b1 and b2 may satisfy b1+b2=0 or b1+b2=1.

In Formula 1, R₁ and R₂ may each be a group represented by Formula 2-1,and R₃ may be a group represented by Formula 2-2:

A₁ to A₄ in Formulae 2-1 and 2-2 may each independently be a benzenegroup, a naphthalene group, a phenanthrene group, a fluoranthene group,a triphenylene group, a pyrene group, a chrysene group, a pyridinegroup, a pyrimidine group, a pyrazine group, a pyridazine group, or atetrazine group.

In one embodiment, A₁ to A₄ may each independently be a benzene group, apyridine group, or a pyrimidine group.

In one embodiment, A₁ to A₄ may each be a benzene group, but embodimentsof the present disclosure are not limited thereto.

In one embodiment, A₅ to A₈ in Formulae 3-1 and 3-2 (provided below) mayeach independently be a benzene group, a pyridine group, or a pyrimidinegroup.

In one embodiment, A₅ to A₈ in Formulae 3-1 and 3-2 (provided below) mayeach be a benzene group, but embodiments of the present disclosure arenot limited thereto.

In Formulae 2-1 and 2-2, Y₁ may be a single bond, O, S, SO₂, N(R₁₉),C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉),

Y₂ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀),S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉),

when Y₂ is O, a group represented by Formula 2-1 and a group representedby Formula 2-2 may be different from each other, and

when Y₂ is a single bond, at least one of R₁₃ and R₁₄ may be a grouprepresented by Formula 3-1 or a group represented by Formula 3-2(provided below).

In one embodiment, when Y₂ is O, Y₁ may be a single bond, S, SO₂,N(R₁₉), C(R₁₉)(R₂₀), or Si(R₁₉)(R₂₀).

In one embodiment, Y₁ may be a single bond, O, S, SO₂, N(R₁₉),C(R₁₉)(R₂₀), or Si(R₁₉)(R₂₀).

In one embodiment, Y₂ may be a single bond, O, S, SO₂, N(R₁₉),C(R₁₉)(R₂₀), or Si(R₁₉)(R₂₀).

b11 to b14 in Formulae 2-1 and 2-2 may each independently be an integerfrom 1 to 8. In one embodiment, b11 to b14 may each independently be aninteger from 1 to 4, but embodiments of the present disclosure are notlimited thereto.

In Formulae 2-1 and 2-2, R₁₁ to R₁₄ may each independently be a grouprepresented by Formula 3-1, a group represented by Formula 3-2,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —S(═O)(Q₁), or —P(═O)(Q₁)(Q₂),

where two or more R₁₁(s) may optionally be linked to form a substitutedor unsubstituted C₅-C₆₀ carbocyclic group or a substituted orunsubstituted C₂-C₆₀ heterocyclic group; two or more R₁₂(s) mayoptionally be linked to form a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₂-C₆₀ heterocyclicgroup; two or more R₁₃(s) may optionally be linked to form a substitutedor unsubstituted C₅-C₆₀ carbocyclic group or a substituted orunsubstituted C₂-C₆₀ heterocyclic group; and two or more R₁₄(s) mayoptionally be linked to form a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₂-C₆₀ heterocyclicgroup.

In one embodiment, R₁₁ to R₁₄ may each independently be selected from:

a group represented by Formula 3-1, a group represented by Formula 3-2,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxygroup, a cyclopentyl group, a cyclohexyl group, a phenyl group, anaphthyl group, a fluorenyl group, a pyridinyl group, a pyrimidyl group,a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group; and

a methyl group, an ethyl group, a propyl group, an isobutyl group, asec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxy group, a cyclopentylgroup, a cyclohexyl group, a phenyl group, a naphthyl group, a fluorenylgroup, a pyridinyl group, a pyrimidyl group, a quinolinyl group, anisoquinolinyl group, a benzoquinolinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a methyl group, an ethyl group, a propyl group, an isobutylgroup, a sec-butyl group, a ter-butyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group.

In one or more embodiments, R₁₁ to R₁₄ may each independently beselected from:

a group represented by Formula 3-1, a group represented by Formula 3-2,hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, an acridyl group, and a carbazolyl group; and

a phenyl group, an acridyl group, and a carbazolyl group, eachsubstituted with at least one substituent selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a methylgroup, an ethyl group, a propyl group, an isobutyl group, a sec-butylgroup, a ter-butyl group, and a C₁-C₂₀ alkoxy group.

In one embodiment, R₁₁ to R₁₄ may each independently be a grouprepresented by Formula 3-1, a group represented by Formula 3-2,hydrogen, deuterium, a phenyl group, an acridyl group substituted with amethyl group, or a carbazolyl group.

Y₃ in Formulae 3-1 and 3-2 may be a single bond, O, S, SO₂, N(R₁₉),C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉). Inone embodiment, Y₃ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀),or Si(R₁₉)(R₂₀), but embodiments of the present disclosure are notlimited thereto.

Y₄ in Formulae 3-1 and 3-2 may be a single bond, O, S, SO₂, N(R₁₉),C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉). Inone embodiment, Y₄ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀),or Si(R₁₉)(R₂₀), but embodiments of the present disclosure are notlimited thereto.

Y₅ in Formulae 3-1 and 3-2 may be a single bond, O, S, SO₂, N(R₁₉),C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉). Inone embodiment, Y₅ may be a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀),or Si(R₁₉)(R₂₀), but embodiments of the present disclosure are notlimited thereto.

R₁₅ to R₂₀ in Formulae 3-1 and 3-2 may each independently be selectedfrom hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substitutedor unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted

C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic,—S(═O)(Q₁), and —P(═O)(Q₁)(Q₂) group.

In one embodiment, R₁₅ to R₂₀ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxygroup, a cyclopentyl group, a cyclohexyl group, a phenyl group, anaphthyl group, a fluorenyl group, a pyridinyl group, a pyrimidyl group,a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group; and

a methyl group, an ethyl group, a propyl group, an isobutyl group, asec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxy group, a cyclopentylgroup, a cyclohexyl group, a phenyl group, a naphthyl group, a fluorenylgroup, a pyridinyl group, a pyrimidyl group, a quinolinyl group, anisoquinolinyl group, a benzoquinolinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a methyl group, an ethyl group, a propyl group, an isobutylgroup, a sec-butyl group, a ter-butyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group.

In one or more embodiments, R₁₅ to R₂₀ may each independently beselected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxygroup, and a phenyl group; and

a phenyl group substituted with at least one substituent selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, a methyl group, an ethyl group, a propyl group, an isobutylgroup, a sec-butyl group, a ter-butyl group, and a C₁-C₂₀ alkoxy group.

In one or more embodiments, R₁₃ to R₁₈ may each independently behydrogen, deuterium, a methyl group, or a phenyl group, but embodimentsof the present disclosure are not limited thereto.

b15 to b18 in Formulae 3-1 and 3-2 may each independently be an integerfrom 1 to 8. In one embodiment, b15 to b18 may each independently be aninteger from 1 to 4, but embodiments of the present disclosure are notlimited thereto.

In one embodiment, the group represented by Formula 3-1 may be a grouprepresented by Formula 3-1-1:

In Formula 3-1-1,

Y₃, R₁₅, and R₁₆ are the same as described herein, and

*indicates a binding site to a neighboring atom.

*in Formulae 2-1, 2-2, 3-1, and 3-2 indicates a binding site to aneighboring atom.

In one embodiment, when Y₁ is a single bond, the group represented byFormula 2-1 may be a group represented by Formula 2-2-1:

In Formula 2-2-1,

R₂₈ may be a group represented by Formula 3-1 or a group represented byFormula 3-2,

definitions of R₂₁ to R₂₇ are each independently the same as thoseprovided in connection with R₁₁ to R₁₄.

In one embodiment, R₂₁ to R₂₇ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, aniso-amyl group, a hexyl group, a C₁-C₂₀ alkoxy group, a cyclopentylgroup, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a naphthyl group, a fluorenyl group,a spiro-bifluorenyl group, a spiro-fluorene-benzofluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenylgroup, a spiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a methyl group, an ethyl group, apropyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, apentyl group, an iso-amyl group, a hexyl group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a naphthyl group, a fluorenyl group,a spiro-bifluorenyl group, a spiro-fluorene-benzofluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group.

In one embodiment, R₂₃ may be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxygroup, a cyclopentyl group, a cyclohexyl group, a phenyl group, anaphthyl group, a fluorenyl group, a pyridinyl group, a pyrimidyl group,a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group; and

a methyl group, an ethyl group, a propyl group, an isobutyl group, asec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxy group, a cyclopentylgroup, a cyclohexyl group, a phenyl group, a naphthyl group, a fluorenylgroup, a pyridinyl group, a pyrimidyl group, a quinolinyl group, anisoquinolinyl group, a benzoquinolinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a methyl group, an ethyl group, a propyl group, an isobutylgroup, a sec-butyl group, a ter-butyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, and

R₂₁, R₂₂, and R₂₄ to R₂₇ may each be hydrogen, but embodiments of thepresent disclosure are not limited thereto.

In one embodiment, the heterocyclic compound represented by Formula 1may be represented by Formula 1-1 or 1-2:

In Formulae 1-1 and 1-2,

definitions of A₁₁, A₁₂, A₂₁, A₂₂, A₃₁, and A₃₂ are each independentlythe same as those provided in connection with A₁ to A₄,

definitions of Y₁₁ and Y₁₃ are the same as that provided in connectionwith Y₁,

definition of Y₁₂ is the same as that provided in connection with Y₂,

and when one of Y₁₁ and Y₁₂ is oxygen (O), the other one of Y₁₁ and Y₁₂is not O,

definitions of R₁₀₁, R₁₀₂, R₁₁₁, R₁₁₂, R₁₂₁, and R₁₂₂ are eachindependently the same as those provided in connection with R₁₁ to R₁₄,and

X₁, Ar₁, and Ar₂ are respectively the same as described in connectionwith Formula 1.

At least one substituent of the substituted C₅-C₆₀ carbocyclic group,the substituted C₂-C₆₀ heterocyclic group, the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group,the substituted C₁-C₆₀ heteroaryl group, the substituted monovalentnon-aromatic condensed polycyclic group, and the substituted monovalentnon-aromatic condensed heteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

where Q₁, Q₂, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may eachindependently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.

In one embodiment, the heterocyclic compound may be one of Compounds 1to 30 illustrated below, but embodiments of the present disclosure arenot limited thereto:

Since the heterocyclic compound represented by Formula 1 includesphosphine oxide (or phosphine sulfide) and has a structure in which theP atom of the phosphine oxide is substituted with N-containing heteroring to form a P—N bond, the heterocyclic compound may have excellentstability, as compared with a compound having no P—N bond. Also, whenthe heterocyclic compound is applied in an organic light-emittingdevice, the lifespan and efficiency of the organic light-emitting devicemay increase.

Therefore, an electronic device, for example, an organic light-emittingdevice, which includes the heterocyclic compound represented by Formula1, may have low driving voltage, high current density, and highefficiency.

Also, the heterocyclic compound represented by Formula 1 is a compoundthat may emit delayed fluorescence, and triplet state excitons, as wellas singlet state excitons, may be used for light emission according toan appropriate combination of substituents. Therefore, an organiclight-emitting device including the heterocyclic compound may haveexcellent luminescent efficiency.

In one embodiment, an organic light-emitting device may include: a firstelectrode; a second electrode facing the first electrode; and an organiclayer that is disposed (e.g., positioned) between the first electrodeand the second electrode, the organic layer including an emission layerand at least one heterocyclic compound of Formula 1.

In one or more embodiments, the first electrode may be an anode.

In one or more embodiments, the second electrode may be a cathode.

In one or more embodiments, the first electrode may be an anode, and thesecond electrode may be a cathode.

In one embodiment, the organic layer may further include a holetransport region between the first electrode and the emission layer, andan electron transport region between the emission layer and the secondelectrode.

In one embodiment, the hole transport region may include at least onelayer selected from a hole injection layer, a hole transport layer, anemission auxiliary layer, and an electron blocking layer.

In one embodiment, the electron transport region may include at leastone selected from a hole blocking layer, an electron transport layer,and an electron injection layer.

In one or more embodiments, the emission layer may include the condensedheterocyclic compound represented by Formula 1. In one embodiment, theemission layer may emit phosphorescence or delayed fluorescence.

In one embodiment, the heterocyclic compound included in the emissionlayer may be a host, and the emission layer may further include aphosphorescent dopant.

In one or more embodiments, the heterocyclic compound included in theemission layer may be a host, and the emission layer may further includea delayed fluorescent dopant satisfying Equation 1 below:|E _(D,S1) −E _(D,T1)|≤0.3 eV.  Equation 1

In Equation 1,

E_(D,S1) is a singlet energy level (eV) of the delayed fluorescentdopant, and

E_(D,T1) is a triplet energy level (eV) of the delayed fluorescentdopant.

Since a difference between the singlet energy level (E_(D,S1)) and thetriplet energy level (E_(D,T1)) of the delayed fluorescent dopant is 0.3eV or less, singlet state excitons and triplet state excitons generatedby an electric field may easily transit to an intermediate state.

In one or more embodiments, the heterocyclic compound included in theemission layer may be a delayed fluorescent dopant satisfying Equation 1below.|E _(D,S1) −E _(D,T1)|≤0.3 eV.  Equation 1

In Equation 1,

E_(D,S1) is a singlet energy level (eV) of the delayed fluorescentdopant, and

E_(D,T1) is a triplet energy level (eV) of the delayed fluorescentdopant.

Since a difference between the singlet energy (E_(D,S1)) and the tripletenergy (E_(D,T1)) of the delayed fluorescent dopant is 0.3 eV or less,singlet state excitons and triplet state excitons generated by anelectric field may easily transit to an intermediate state.

In one or more embodiments, the heterocyclic compound included in theemission layer may be a delayed fluorescent dopant, the emission layermay further include a host, and the delayed fluorescent dopant and thehost may satisfy Equation 2 or 3 below:|E _(H,HOMO) −E _(D,HOMO)|≤0.5 eV  Equation 2|E _(H,LUMO) −E _(D,LUMO)|≤0.5 eV  Equation 3

In Equations 2 and 3,

E_(H, HOMO) is a highest occupied molecular orbital level of the host,

E_(D, HOMO) is a highest occupied molecular orbital level of the dopant,

E_(H, LUMO) is a lowest unoccupied molecular orbital level of the host,and

E_(D, LUMO) is a lowest unoccupied molecular orbital level of thedopant.

Since a difference in highest occupied molecular orbital levels orlowest unoccupied molecular orbital levels of the delayed fluorescentdopant (e.g., the heterocyclic compound) and the host is 0.5 eV or less,charge transfer from the host to the delayed fluorescent dopant may befacilitated. Therefore, an organic light-emitting device including theheterocyclic compound as the delayed fluorescent dopant may haveexcellent luminescent efficiency.

For example, the host may include a silicon-based compound, acarbazole-based compound, or a phosphine oxide-based compound:

According to an embodiment, the host may be one of Compounds H101 toH106 below:

At least one layer selected from the electron transport layer and theelectron injection layer may include an alkali metal, an alkaline earthmetal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, ora combination thereof.

The organic light-emitting device including the heterocyclic compoundmay have low driving voltage, high current density, and high efficiency.

A synthesis method for the heterocyclic compound represented by Formula1 should be apparent to those of ordinary skill in the art by referringto the following examples (provided below).

At least one of the heterocyclic compounds of Formula 1 may be usedbetween a pair of electrodes of an organic light-emitting device. Forexample, the heterocyclic compound may be included in at least one layerselected from a hole transport region and an emission layer. In one ormore embodiments, the heterocyclic compound of Formula 1 may be used asa material for a capping layer located outside a pair of electrodes ofan organic light-emitting device.

For example, an organic light-emitting device may include: a firstelectrode; a second electrode facing the first electrode; and an organiclayer between the first electrode and the second electrode, the organiclayer including an emission layer, wherein the organic layer includes atleast one heterocyclic compound represented by Formula 1.

The reference to a layer including at least one heterocyclic compound,as used herein, may refer to a layer including one or more of the sameheterocyclic compound represented by Formula 1 and/or a layer includingtwo or more different heterocyclic compounds represented by Formula 1.

For example, the organic layer may include, as the heterocycliccompound, only Compound 1. In this embodiment, Compound 1 may exist inan emission layer of the organic light-emitting device. In anotherexample, the organic layer may include, as the heterocyclic compound,Compound 1 and Compound 2. In this embodiment, Compound 1 and Compound 2may both exist in the same layer (e.g., Compound 1 and Compound 2 mayboth exist in an emission layer), or in different layers (e.g., Compound1 may exist in an emission layer and Compound 2 may exist in an electrontransport layer).

In one embodiment,

the first electrode of the organic light-emitting device may be ananode,

the second electrode of the organic light-emitting device may be acathode,

the organic layer of the organic light-emitting device may furtherinclude a hole transport region between the first electrode and theemission layer and an electron transport region between the emissionlayer and the second electrode,

the hole transport region may include at least one layer selected from ahole injection layer, a hole transport layer, a buffer layer, anemission auxiliary layer, and an electron blocking layer, and

the electron transport region may include at least one layer selectedfrom a hole blocking layer, an electron transport layer, and an electroninjection layer. The electron transport region may include theheterocyclic compound represented by Formula 1.

In one embodiment, the electron transport region of the organiclight-emitting device may include an electron transport layer and anelectron injection layer, and at least one of the electron transportlayer and the electron injection layer may include the heterocycliccompound represented by Formula 1. However, embodiments of the presentdisclosure are not limited thereto.

In the organic light-emitting device, at least one layer selected fromthe electron transport layer and the electron injection layer mayinclude an alkali metal, an alkaline earth metal, a rare earth metal, analkali metal compound, an alkaline earth-metal compound, a rare earthmetal compound, an alkali metal complex, an alkaline earth-metalcomplex, a rare earth metal complex, or a combination thereof.

In the organic light-emitting device, the emission layer may include adopant and a host, and the host may include at least one compoundselected from an anthracene-based compound, a pyrene-based compound, anda spiro-bifluorene-based compound

The term “organic layer” used herein may refer to a single layer and/ora plurality of layers disposed (e.g., positioned) between the firstelectrode and the second electrode of the organic light-emitting device.A material included in the “organic layer” is not limited to an organicmaterial.

The drawing is a schematic view of an organic light-emitting device 10according to an embodiment. The organic light-emitting device 10includes a first electrode 110, an organic layer 150, and a secondelectrode 190.

Hereinafter, the structure of the organic light-emitting device 10according to an embodiment and a method of manufacturing the organiclight-emitting device 10 will be described in connection with thedrawing.

In the drawing, a substrate may be additionally disposed under the firstelectrode 110 or above the second electrode 190. The substrate may be aglass substrate or a plastic substrate, each having excellent (orsuitable) mechanical strength, thermal stability, transparency, surfacesmoothness, ease of handling, and/or water resistance.

The first electrode 110 may be formed by depositing or sputtering amaterial for forming the first electrode 110 on the substrate. When thefirst electrode 110 is an anode, the material for forming the firstelectrode may be selected from materials with a high work function so asto facilitate hole injection.

The first electrode 110 may be a reflective electrode, asemi-transmissive electrode, or a transmissive electrode. When the firstelectrode 110 is a transmissive electrode, a material for forming thefirst electrode may be selected from indium tin oxide (ITO), indium zincoxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), and a combinationthereof, but embodiments of the present disclosure are not limitedthereto.

In one or more embodiments, when the first electrode 110 is asemi-transmissive electrode or a reflective electrode, a material forforming the first electrode may be selected from magnesium (Mg), silver(Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca),magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), and a combinationthereof, but embodiments of the present disclosure are not limitedthereto.

The first electrode 110 may have a single-layered structure, or amulti-layered structure including two or more layers. For example, thefirst electrode 110 may have a three-layered structure of ITO/Ag/ITO,but the structure of the first electrode 110 is not limited thereto.

The organic layer 150 may be disposed on the first electrode 110. Theorganic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport regionbetween the first electrode 110 and the emission layer, and an electrontransport region between the emission layer and the second electrode190.

The hole transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from ahole injection layer, a hole transport layer, an emission auxiliarylayer, and an electron blocking layer.

For example, the hole transport region may have a single-layeredstructure including a single layer including a plurality of differentmaterials, or a multi-layered structure having a hole injectionlayer/hole transport layer structure, a hole injection layer/holetransport layer/emission auxiliary layer structure, a hole injectionlayer/emission auxiliary layer structure, a hole transportlayer/emission auxiliary layer structure, or a hole injection layer/holetransport layer/electron blocking layer structure, wherein for eachstructure, constituting layers are sequentially stacked from the firstelectrode 110 in this stated order, but the structure of the holetransport region is not limited thereto.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB(NPD), β-NPB, TPD, spiro-TPD, spiro-NPB,methylated NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine(TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (PANT/CSA),polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound representedby Formula 201, and a compound represented by Formula 202:

In Formulae 201 and 202,

L₂₀₁ to L₂₀₄ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

L₂₀₅ may be selected from *—O—*′, *—S—*′, *—N(Q₂₀₁)-*′, a substituted orunsubstituted C₁-C₂₀ alkylene group, a substituted or unsubstitutedC₂-C₂₀ alkenylene group, a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xa1 to xa4 may each independently be an integer from 0 to 3,

xa5 may be an integer from 1 to 10, and

R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group.

For example, in Formula 202, R₂₀₁ and R₂₀₂ may optionally be linked toform a single bond, a dimethyl-methylene group, or a diphenyl-methylenegroup; and R₂₀₃ and R₂₀₄ may optionally be linked to form a single bond,a dimethyl-methylene group, or a diphenyl-methylene group.

In one embodiment, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from:

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, xa1 to xa4 may each independently be 0, 1,or 2.

In one or more embodiments, xa5 may be 1, 2, 3, or 4.

In one or more embodiments, R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independentlybe selected from:

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may be the same as described herein.

In one or more embodiments, at least one of R₂₀₁ to R₂₀₃ in Formula 201may be selected from:

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkylgroup, a phenyl group substituted with —F, a naphthyl group, a fluorenylgroup, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranylgroup, and a dibenzothiophenyl group,

but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, in Formula 202, i) R₂₀₁ and R₂₀₂ may belinked via a single bond, and/or ii) R₂₀₃ and R₂₀₄ may be linked via asingle bond.

In one or more embodiments, at least one of R₂₀₁ to R₂₀₄ in Formula 202may be selected from:

a carbazolyl group; and

a carbazolyl group substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, acarbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group,

but embodiments of the present disclosure are not limited thereto.

The compound represented by Formula 201 may be represented by Formula201A:

In one embodiment, the compound represented by Formula 201 may berepresented by Formula 201A(1) below, but embodiments of the presentdisclosure are not limited thereto:

In one embodiment, the compound represented by Formula 201 may berepresented by Formula 201A-1 below, but embodiments of the presentdisclosure are not limited thereto:

In one embodiment, the compound represented by Formula 202 may berepresented by Formula 202A:

In one embodiment, the compound represented by Formula 202 may berepresented by Formula 202A-1:

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

definitions for L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ are thesame as those provided herein,

definitions of R₂₁₁ and R₂₁₂ may each independently be the same as thatprovided in connection with R₂₀₃,

R₂₁₃ to R₂₁₇ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group.

The hole transport region may include at least one compound selectedfrom Compounds HT1 to HT39, but embodiments of the present disclosureare not limited thereto:

A thickness of the hole transport region may be in a range of about 100Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When thehole transport region includes at least one of a hole injection layerand a hole transport layer, a thickness of the hole injection layer maybe in a range of about 100 Å to about 9,000 Å, for example, about 100 Åto about 1,000 Å, and a thickness of the hole transport layer may be ina range of about 50 Å to about 2,000 Å, for example about 100 Å to about1,500 Å. When the thicknesses of the hole transport region, the holeinjection layer, and the hole transport layer are within any of theseranges, satisfactory (or suitable) hole transporting characteristics maybe obtained without a substantial increase in driving voltage.

The emission auxiliary layer may increase light-emission efficiency bycompensating for an optical resonance distance according to thewavelength of light emitted by an emission layer; and the electronblocking layer may block the flow of electrons from an electrontransport region. The emission auxiliary layer and the electron blockinglayer may include any of the suitable materials as described above.

The hole transport region may further include, in addition to thematerials described above, a charge-generation material for theimprovement of conductive properties. The charge-generation material maybe homogeneously or non-homogeneously dispersed in the hole transportregion.

The charge-generation material may be, for example, a p-dopant.

In one embodiment, the p-dopant may have a LUMO of −3.5 eV or less.

The p-dopant may include at least one selected from a quinonederivative, a metal oxide, and a cyano group-containing compound, butembodiments of the present disclosure are not limited thereto.

For example, the p-dopant may include at least one selected from:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and/or2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide and/or molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

a compound represented by Formula 221 below,

but embodiments of the present disclosure are not limited thereto:

In Formula 221,

R₂₂₁ to R₂₂₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, provided that at leastone of R₂₂₁ to R₂₂₃ has at least one substituent selected from a cyanogroup, —F, —Cl, —Br, —I, a C₁-C₂₀ alkyl group substituted with —F, aC₁-C₂₀ alkyl group substituted with —Cl, a C₁-C₂₀ alkyl groupsubstituted with Br, and a C₁-C₂₀ alkyl group substituted with —I.

When the organic light-emitting device 10 is a full-color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, or a blue emission layer,according to a sub-pixel. In one or more embodiments, the emission layermay have a stacked structure of two or more layers selected from a redemission layer, a green emission layer, and a blue emission layer, inwhich the two or more layers contact each other or are separated fromeach other. In one or more embodiments, the emission layer may includetwo or more materials selected from a red light-emitting material, agreen light-emitting material, and a blue light-emitting material, inwhich the two or more materials are mixed with each other in a singlelayer to emit white light.

The emission layer may include a host and a dopant. The dopant mayinclude at least one selected from a phosphorescent dopant and afluorescent dopant.

An amount of the dopant in the emission layer may be in a range of about0.01 parts to about 15 parts by weight, based on 100 parts by weight ofthe host, but embodiments of the present disclosure are not limitedthereto.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, for example, about 200 Å to about 600 Å. When thethickness of the emission layer is within this range, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

The host may include the heterocyclic compound represented by Formula 1.

In one or more embodiments, the host may include a silicon-basedcompound, a carbazole-based compound, or a phosphine oxide-basedcompound.

For example, the host may be one of Compounds H101 to H106 below:

In one or more embodiments, the host may include a compound representedby Formula 301 below:[Ar ₃₀₁]_(xb11)-[(L ₃₀₁)_(xb1)-R ₃₀₁]_(xb21).  Formula 301In Formula 301,

Ar₃₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xb11 may be 1, 2, or 3,

L₃₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xb1 may be an integer from 0 to 5,

R₃₀₁ may be selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), —N(Q₃₀₁)(Q₃₀₂),—B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), and —P(═O)(Q₃₀₁)(Q₃₀₂),

xb21 may be an integer from 1 to 5, and

Q₃₀₁ to 0₃₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group, but embodiments of the presentdisclosure are not limited thereto.

In one embodiment, Ar₃₀₁ in Formula 301 may be selected from:

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup; and

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂),—C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group, but embodiments of the present disclosureare not limited thereto.

When xb11 in Formula 301 is two or more, two or more Ar₃₀₁(s) may belinked via a single bond.

In one or more embodiments, the compound represented by Formula 301 maybe represented by Formula 301-1 or Formula 301-2:

In Formulae 301-1 and 301-2,

A₃₀₁ to A₃₀₄ may each independently be selected from a benzene group, anaphthalene group, a phenanthrene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a pyridine group,a pyrimidine group, an indene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,an indole group, a carbazole group, a benzocarbazole group, adibenzocarbazole group, a furan group, a benzofuran group, adibenzofuran group, a naphthofuran group, a benzonaphthofuran group, adinaphthofuran group, a thiophene group, a benzothiophene group, adibenzothiophene group, a naphthothiophene group, abenzonaphthothiophene group, and a dinaphthothiophene group,

X₃₀₁ may be O, S, or N-[(L₃₀₄)_(xb4)-R₃₀₄],

R₃₁₁ to R₃₁₄ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

xb22 and xb23 may each independently be 0, 1, or 2,

L₃₀₁, xb1, R₃₀₁, and Q₃₁ to Q₃₃ may be the same as described herein,

definitions of L₃₀₂ to L₃₀₄ may each independently be the same as thatprovided in connection with L₃₀₁,

definitions of xb2 to xb4 may each independently be the same as thatprovided in connection with xb1, and

definitions of R₃₀₂ to R₃₀₄ may each independently be the same as thatprovided in connection with R₃₀₁.

For example, L₃₀₁ to L₃₀₄ in Formulae 301, 301-1, and 301-2 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazophridinyl group, an imidazopyrimidinylgroup, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ are the same as described herein.

In one embodiment, R₃₀₁ to R₃₀₄ in Formulae 301, 301-1, and 301-2 mayeach independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁) and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ are the same as described herein.

In one embodiment, the host may include an alkaline earth-metal complex.

For example, the host may be selected from a Be complex (e.g., CompoundH55), a Mg complex, and a Zn complex.

The host may include at least one selected from9,10-di(2-naphthyl)anthracene (ADN),2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN),9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN),4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene(mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55,but embodiments of the present disclosure are not limited thereto:

The phosphorescent dopant may include an organometallic complexrepresented by Formula 401:

In Formulae 401 and 402,

M may be selected from iridium (Ir), platinum (Pt), palladium (Pd),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), rhodium (Rh), and thulium (Tm),

L₄₀₁ may be selected from ligands represented by Formula 402, and xc1may be 1, 2, or 3, wherein, when xc1 is two or more, two or more L₄₀₁(S)may be identical to or different from each other,

L₄₀₂ may be an organic ligand, and xc2 may be an integer from 0 to 4,wherein, when xc2 is two or more, two or more L₄₀₂(s) may be identicalto or different from each other,

X₄₀₁ to X₄₀₄ may each independently be nitrogen or carbon,

X₄₀₁ and X₄₀₃ may be linked via a single bond or a double bond, and X₄₀₂and X₄₀₄ may be linked via a single bond or a double bond,

A₄₀₁ and A₄₀₂ may each independently be a C₅-C₆₀ carbocyclic group or aC₁-C₆₀ heterocyclic group,

X₄₀₅ may be a single bond, *—O—*′, *—S—*′, *—C(═O)-*′, *—N(Q₄₁₁)-*′,*—C(Q₄₁₁)(Q₄₁₂)-′, *—C(Q₄₁₁)═C(Q₄₁₂)-′, *—C(Q₄₁₁)=*′, or *═C(Q₄₁₁)=*′,wherein Q₄₁₁ and Q₄₁₂ may each independently be hydrogen, deuterium, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, or a naphthyl group,

X₄₀₆ may be a single bond, O, or S,

R₄₀₁ and R₄₀₂ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₂₀ alkyl group, a substituted orunsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂),—B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂),wherein Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a C₆-C₂₀ aryl group, and a C₁-C₂₀heteroaryl group,

xc11 and xc12 may each independently be an integer from 0 to 10, and

*and *′ in Formula 402 each indicate a binding site to M in Formula 401.

In one embodiment, A₄₀₁ and A₄₀₂ in Formula 402 may each independentlybe a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, an indene group, a pyrrole group, a thiophenegroup, a furan group, an imidazole group, a pyrazole group, a thiazolegroup, an isothiazole group, an oxazole group, an isoxazole group, apyridine group, a pyrazine group, a pyrimidine group, a pyridazinegroup, a quinoline group, an isoquinoline group, a benzoquinoline group,a quinoxaline group, a quinazoline group, a carbazole group, abenzimidazole group, a benzofuran group, a benzothiophene group, anisobenzothiophene group, a benzoxazole group, an isobenzoxazole group, atriazole group, a tetrazole group, an oxadiazole group, a triazinegroup, a dibenzofuran group, and a dibenzothiophene group.

In one or more embodiments, in Formula 402, i) X₄₀₁ may be nitrogen, andX₄₀₂ may be carbon, or ii) X₄₀₁ and X₄₀₂ may both be nitrogen.

In one or more embodiments, R₄₀₁ and R₄₀₂ in Formula 402 may eachindependently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a phenyl group, a naphthyl group, a cyclopentyl group,a cyclohexyl group, an adamantanyl group, a norbornanyl group, and anorbornenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

—Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁), —

S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂), and

Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, and anaphthyl group, but embodiments of the present disclosure are notlimited thereto.

In one or more embodiments, when xc1 in Formula 401 is two or more, twoor more L₄₀₁(s) may optionally be linked via a linking group X₄₀₇, ortwo A₄₀₂(s) in two or more L₄₀₁(S) may optionally be linked via alinking group X₄₀₈ (see e.g., Compounds PD1 to PD4 and PD7). X₄₀₇ andX₄₀₈ may each independently be a single bond, *—O—*′,*—S—*′, *—C(═O)—*′,*—N(Q₄₁₃)-*′, *—C(Q₄₁₃)(Q₄₁₄)—*′, or *—C(Q₄₁₃)═C(Q₄₁₄)-*′ (wherein Q₄₁₃and Q₄₁₄ may each independently be hydrogen, deuterium, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, or a naphthyl group), but embodiments of the presentdisclosure are not limited thereto.

L₄₀₂ in Formula 401 may be a monovalent, divalent, or trivalent organicligand. For example, L₄₀₂ may be selected from halogen, diketone (e.g.,acetylacetonate), carboxylic acid (e.g., picolinate), —C(═O),isonitrile, —CN, and phosphorus (e.g., phosphine and/or phosphite), butembodiments of the present disclosure are not limited thereto.

In one or more embodiments, the phosphorescent dopant may be selectedfrom, for example, Compounds PD1 to PD25, but embodiments of the presentdisclosure are not limited thereto:

The fluorescent dopant may include an arylamine compound or astyrylamine compound.

The fluorescent dopant may include a compound represented by Formula 501below:

In Formula 501,

Ar₅₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

L₅₀₁ to L₅₀₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xd1 to xd3 may each independently be an integer from 0 to 3,

R₅₀₁ and R₅₀₂ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,and

xd4 may be an integer from 1 to 6.

In one embodiment, Ar₅₀₁ in Formula 501 may be selected from:

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup; and

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, L₅₀₁ to L₅₀₃ in Formula 501 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and pyridinylene group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group.

In one or more embodiments, R₅₀₁ and R₅₀₂ in Formula 501 may eachindependently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃), and

Q₃₁ to Q₃₃ may be selected from a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxygroup, a phenyl group, a biphenyl group, a terphenyl group, and anaphthyl group.

In one or more embodiments, xd4 in Formula 501 may be 2, but embodimentsof the present disclosure are not limited thereto.

For example, the fluorescent dopant may be selected from Compounds FD1to FD22:

In one or more embodiments, the fluorescent dopant may be selected fromthe following compounds, but embodiments of the present disclosure arenot limited thereto:

The electron transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure including aplurality of layers including a plurality of different materials.

The electron transport region may include at least one selected from abuffer layer, a hole blocking layer, an electron control layer, anelectron transport layer, and an electron injection layer, butembodiments of the present disclosure are not limited thereto.

For example, the electron transport region may have an electrontransport layer/electron injection layer structure, a hole blockinglayer/electron transport layer/electron injection layer structure, anelectron control layer/electron transport layer/electron injection layerstructure, or a buffer layer/electron transport layer/electron injectionlayer structure, wherein for each structure, constituting layers aresequentially stacked from an emission layer. However, embodiments of thestructure of the electron transport region are not limited thereto.

The electron transport region (e.g., a buffer layer, a hole blockinglayer, an electron control layer, and/or an electron transport layer inthe electron transport region) may include a metal-free compoundcontaining at least one 7 electron-depleted nitrogen-containing ring.

As used herein, the “7 electron-depleted nitrogen-containing ring” mayrefer to a C₁-C₆₀ heterocyclic group including at least one *—N═*′moiety as a ring-forming moiety.

For example, the “π electron-depleted nitrogen-containing ring” may bei) a 5-membered to 7-membered heteromonocyclic group including at leastone *—N═*′ moiety, ii) a heteropolycyclic group in which two or more5-membered to 7-membered heteromonocyclic groups each including at leastone *—N═*′ moiety are condensed with each other, or iii) aheteropolycyclic group in which at least one 5-membered to 7-memberedheteromonocyclic group including at least one *—N═*′ moiety, iscondensed with at least one C₅-C₆₀ carbocyclic group.

Examples of the π electron-depleted nitrogen-containing ring include animidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, anisoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, anindazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, aphthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline,a phenanthridine, an acridine, a phenanthroline, a phenazine, abenzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, atriazole, a tetrazole, an oxadiazole, a triazine, thiadiazole, animidazopyridine, an imidazopyrimidine, and an azacarbazole, butembodiments of the present disclosure are not limited thereto.

For example, the electron transport region may include a compoundrepresented by Formula 601:[Ar ₆₀₁]_(xe11)-[(L ₆₀₁)_(xe1)-R ₆₀₁]_(xe21).  Formula 601

In Formula 601,

Ar₆₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xe11 may be 1, 2, or 3,

L₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xe1 may be an integer from 0 to 5,

R₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃), —C(═O)(Q₆₀₁),—S(═O)₂(Q₆₀₁), and —P(═O)(Q₆₀₁)(Q₆₀₂),

Q₆₀₁ to Q₆₀₃ may each independently be a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or anaphthyl group, and

xe21 may be an integer from 1 to 5.

In one embodiment, at least one selected from xe11 number of Ar₆₀₁(s)and xe21 number of R₆₀₁(S) may include the 7 electron-depletednitrogen-containing ring.

In one embodiment, Ar₆₀₁ in Formula 601 may be selected from:

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an iso-benzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group; and

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an iso-benzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

When xe11 in Formula 601 is two or more, two or more Ar₆₀₁(s) may belinked via a single bond.

In one or more embodiments, Ar₆₀₁ in Formula 601 may be an anthracenegroup.

In one or more embodiments, the compound represented by Formula 601 maybe represented by Formula 601-1:

In Formula 601-1,

X₆₁₄ may be N or C(R₆₁₄), X₆₁₅ may be N or C(R₆₁₅), X₆₁₆ may be N orC(R₆₁₆), and at least one of X₆₁₄ to X₆₁₆ may be N,

definitions of L₆₁₁ to L₆₁₃ may each independently be the same as thatprovided in connection with L₆₀₁,

definitions of xe611 to xe613 may each independently be the same as thatprovided in connection with xe1,

definitions of R₆₁₁ to R₆₁₃ may each independently be the same as thatprovided in connection with R₆₀₁,

R₆₁₄ to R₆₁₆ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In one embodiment, L₆₀₁ and L₆₁₁ to L₆₁₃ in Formulae 601 and 601-1 mayeach independently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group,

but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, xe1 and xe611 to xe613 in Formulae 601 and601-1 may each independently be 0, 1, or 2.

In one or more embodiments, R₆₀₁ and R₆₁₁ to R₆₁₃ in Formulae 601 and601-1 may each independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

—S(═O)₂(Q₆₀₁) and —P(═O)(Q₆₀₁)(Q₆₀₂), and

Q₆₀₁ and Q₆₀₂ are the same as described herein.

The electron transport region may include at least one compound selectedfrom Compounds ET1 to ET36, but embodiments of the present disclosureare not limited thereto:

In one or more embodiments, the electron transport region may include atleast one compound selected from2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP),4,7-diphenyl-1,10-phenanthroline (Bphen), Alq₃, BAlq,3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ), and NTAZ:

A thickness of each of the buffer layer, the hole blocking layer, and/orthe electron control layer may be in a range of about 20 Å to about1,000 Å, for example, about 30 Å to about 300 Å. When the thickness ofeach of the buffer layer, the hole blocking layer, and/or the electroncontrol layer is within the range described above, the buffer layer, thehole blocking layer, and/or the electron control layer may havesatisfactory (or suitable) hole blocking or electron controllingcharacteristics without a substantial increase in driving voltage.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Whenthe thickness of the electron transport layer is within the rangedescribed above, the electron transport layer may have satisfactory (orsuitable) electron transport characteristics without a substantialincrease in driving voltage.

The electron transport region (e.g., the electron transport layer in theelectron transport region) may further include, in addition to thematerials described above, a metal-containing material.

The metal-containing material may include at least one selected from analkali metal complex and an alkaline earth metal complex. The alkalimetal complex may include a metal ion selected from a Li ion, a Na ion,a K ion, a Rb ion, and a Cs ion; and the alkaline earth metal complexmay include a metal ion selected from a Be ion, a Mg ion, a Ca ion, a Srion, and a Ba ion. A ligand coordinated with the metal ion of the alkalimetal complex or the alkaline earth-metal complex may be selected from ahydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, ahydroxy acridine, a hydroxy phenanthridine, a hydroxy phenyloxazole, ahydroxy phenylthiazole, a hydroxy diphenyloxadiazole, a hydroxydiphenylthiadiazole, a hydroxy phenylpyridine, a hydroxyphenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, aphenanthroline, and a cyclopentadiene, but embodiments of the presentdisclosure are not limited thereto.

For example, the metal-containing material may include a Li complex. TheLi complex may include, for example, Compound ET-D1 (lithium quinolate,LiQ) or Compound ET-D2:

The electron transport region may include an electron injection layerthat facilitates injection of electrons from the second electrode 190.The electron injection layer may directly contact the second electrode190.

The electron injection layer may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron injection layer may include an alkali metal, an alkalineearth metal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, ora combination thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In oneembodiment, the alkali metal may be Li, Na, or Cs. In one or moreembodiments, the alkali metal may be Li or Cs, but embodiments of thepresent disclosure are not limited thereto.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare earth metal may be selected from Sc, Y, Ce, Tb, Yb, and Gd.

The alkali metal compound, the alkaline earth-metal compound, and therare earth metal compound may be an oxide and/or a halide (e.g.,fluoride, chloride, bromide, and/or iodide) of the alkali metal, thealkaline earth metal, and the rare earth metal, respectively.

For example, the alkali metal compound may be selected from alkali metaloxides (such as Li₂O, Cs₂O and/or K₂O) and alkali metal halides (such asLiF, NaF, CsF, KF, LiI, NaI, CsI, KI and/or RbI). In one embodiment, thealkali metal compound may be selected from LiF, Li₂O, NaF, LiI, NaI,CsI, and KI, but embodiments of the present disclosure are not limitedthereto.

The alkaline earth-metal compound may be selected from alkalineearth-metal oxides, such as BaO, SrO, CaO, Ba_(x)Sr_(1-x)O (0<x<1)and/or Ba_(x)Ca_(1-x)O(0<x<1). In one embodiment, the alkalineearth-metal compound may be selected from BaO, SrO, and CaO, butembodiments of the present disclosure are not limited thereto.

The rare earth metal compound may be selected from YbF₃, ScF₃, ScO₃,Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In one embodiment, the rare earth metalcompound may be selected from YbF₃, ScF₃, TbF₃, YbI₃, ScI₃, and TbI₃,but embodiments of the present disclosure are not limited thereto.

The alkali metal complex, the alkaline earth metal complex, and the rareearth metal complex may respectively include an ion of an alkali metal,an alkaline earth metal, and a rare earth metal as described above. Aligand coordinated with the metal ion of the alkali metal complex, thealkaline earth metal complex, or the rare earth metal complex may beselected from a hydroxy quinoline, a hydroxy isoquinoline, a hydroxybenzoquinoline, a hydroxy acridine, a hydroxy phenanthridine, a hydroxyphenyloxazole, a hydroxy phenylthiazole, a hydroxy diphenyloxadiazole, ahydroxy diphenylthiadiazole, a hydroxy phenylpyridine, a hydroxyphenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, aphenanthroline, and a cyclopetadiene, but embodiments of the presentdisclosure are not limited thereto.

The electron injection layer may include an alkali metal, an alkalineearth metal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, ora combination thereof, as described above. In one or more embodiments,the electron injection layer may further include an organic material.When the electron injection layer further includes an organic material,the alkali metal, the alkaline earth metal, the rare earth metal, thealkali metal compound, the alkaline earth-metal compound, the rare earthmetal compound, the alkali metal complex, the alkaline earth-metalcomplex, the rare earth metal complex, or a combination thereof may behomogeneously or non-homogeneously dispersed in a matrix including theorganic material.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within the range describedabove, the electron injection layer may have satisfactory (or suitable)electron injection characteristics without a substantial increase indriving voltage.

The second electrode 190 may be disposed on the organic layer 150 havingthe structure according to embodiments of the present disclosure. Thesecond electrode 190 may be a cathode, which is an electron injectionelectrode, and in this regard, a material for forming the secondelectrode 190 may be selected from metals, alloys, electricallyconductive compounds, and combinations thereof, which have a relativelylow work function.

The second electrode 190 may include at least one selected from lithium(Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium(Al-Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver(Mg—Ag), ITO, and IZO, but embodiments of the present disclosure are notlimited thereto. The second electrode 190 may be a transmissiveelectrode, a semi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have a single-layered structure, or amulti-layered structure including two or more layers.

Hereinbefore, the organic light-emitting device has been described withreference to the drawing, but embodiments of the present disclosure arenot limited thereto.

Layers constituting the hole transport region, the emission layer, andlayers constituting the electron transport region may each independentlybe formed in the respective region by using one or more suitable methodsselected from vacuum deposition, spin coating, casting,Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, andlaser-induced thermal imaging.

When any of the layers constituting the hole transport region, theemission layer, and layers constituting the electron transport regionare formed by vacuum deposition, for example, the vacuum deposition maybe performed at a deposition temperature of about 100° C. to about 500°C., at a vacuum degree of about 10⁻⁸ torr to about 10⁻³ torr, and at adeposition rate of about 0.01 Å/sec to about 100 Å/sec, taking intoaccount the characteristics of the material to be included in the layerto be formed, and the desired structure of the layer to be formed.

When any of the layers constituting the hole transport region, theemission layer, and layers constituting the electron transport regionare formed by spin coating, the spin coating may be performed at acoating speed of about 2,000 rpm to about 5,000 rpm and at a heattreatment temperature of about 80° C. to 200° C., taking into accountthe characteristics of the material to be included in the layer to beformed, and the desired structure of the layer to be formed.

The term “C₁-C₆₀ alkyl group” as used herein may refer to a linear orbranched aliphatic saturated hydrocarbon monovalent group having 1 to 60carbon atoms, and non-limiting examples thereof include a methyl group,an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, atert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group.The term “C₁-C₆₀ alkylene group” as used herein may refer to a divalentgroup having the same structure as the C₁-C₆₀ alkyl group.

The term “C₂-C₆₀ alkenyl group” as used herein may refer to ahydrocarbon group having at least one carbon-carbon double bond in themiddle and/or at either terminus of the C₂-C₆₀ alkyl group, andnon-limiting examples thereof include an ethenyl group, a propenylgroup, and a butenyl group. The term “C₂-C₆₀ alkenylene group” as usedherein may refer to a divalent group having the same structure as theC₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein may refer to ahydrocarbon group having at least one carbon-carbon triple bond in themiddle and/or at either terminus of the C₂-C₆₀ alkyl group, andnon-limiting examples thereof include an ethynyl group and a propynylgroup. The term “C₂-C₆₀ alkynylene group” as used herein may refer to adivalent group having the same structure as the C₂-C₆₀ alkynyl group.

The term “C₁-C₆₀ alkoxy group” as used herein may refer to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group),and non-limiting examples thereof include a methoxy group, an ethoxygroup, and an isopropoxy group.

The term “C₃-C₁₀ cycloalkyl group” as used herein may refer to amonovalent saturated hydrocarbon monocyclic group having 3 to 10 carbonatoms, and non-limiting examples thereof include a cyclopropyl group, acyclobutyl group, a cyclopentyl group, a cyclohexyl group, and acycloheptyl group. The term “C₃-C₁₀ cycloalkylene group” as used hereinmay refer to a divalent group having the same structure as the C₃-C₁₀cycloalkyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein may refer to amonovalent monocyclic group having at least one heteroatom selected fromN, O, Si, P, and S as a ring-forming atom and 1 to 10 carbon atoms, andnon-limiting examples thereof include a 1,2,3,4-oxatriazolidinyl group,a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term“C₁-C₁₀ heterocycloalkylene group” as used herein may refer to adivalent group having the same structure as the C₁-C₁₀ heterocycloalkylgroup.

The term “C₃-C₁₀ cycloalkenyl group” as used herein may refer to amonovalent monocyclic group that has 3 to 10 carbon atoms and at leastone carbon-carbon double bond in the ring thereof, but does not havearomaticity; and non-limiting examples thereof include a cyclopentenylgroup, a cyclohexenyl group, and a cycloheptenyl group. The term “C₃-C₁₀cycloalkenylene group” as used herein may refer to a divalent grouphaving the same structure as the C₃-C₁₀ cycloalkenyl group.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein may refer to amonovalent monocyclic group that has at least one heteroatom selectedfrom N, O, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms,and at least one carbon-carbon double bond in its ring, but does nothave aromaticity. Non-limiting examples of the C₁-C₁₀ heterocycloalkenylgroup include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term“C₁-C₁₀ heterocycloalkenylene group” as used herein may refer to adivalent group having the same structure as the C₁-C₁₀heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein may refer to a monovalentgroup having a carbocyclic aromatic system having 6 to 60 carbon atoms,and a C₆-C₆₀ arylene group used herein may refer to a divalent grouphaving a carbocyclic aromatic system having 6 to 60 carbon atoms.Non-limiting examples of the C₆-C₆₀ aryl group include a phenyl group, anaphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenylgroup, and a chrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀arylene group each independently include two or more rings, therespective rings may be fused (condensed) to each other.

The term “C₁-C₆₀ heteroaryl group” as used herein may refer to amonovalent group having a carbocyclic aromatic system that has at leastone heteroatom selected from N, O, Si, P, and S as a ring-forming atom,in addition to 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylenegroup” as used herein may refer to a divalent group having a carbocyclicaromatic system that has at least one heteroatom selected from N, O, Si,P, and S as a ring-forming atom, in addition to 1 to 60 carbon atoms.Non-limiting examples of the C₁-C₆₀ heteroaryl group include a pyridinylgroup, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group. Whenthe C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group eachindependently include two or more rings, the respective rings may becondensed (fused) with each other.

The term “C₆-C₆₀ aryloxy group” as used herein may refer to a grouprepresented by —OA₁₀₂ (wherein A₁₀₂ is the C₆-C₆₀ aryl group), and aC₆-C₆₀ arylthio group used herein may refer to a group represented by—SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

The term “monovalent non-aromatic condensed polycyclic group” as usedherein may refer to a monovalent group having two or more ringscondensed (fused) with each other, only carbon atoms as ring-formingatoms (e.g., having 8 to 60 carbon atoms), and no overall aromaticity inits entire molecular structure. A non-limiting example of the monovalentnon-aromatic condensed polycyclic group is a fluorenyl group. The term“divalent non-aromatic condensed polycyclic group,” used herein, mayrefer to a divalent group having the same structure as the monovalentnon-aromatic condensed polycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” asused herein may refer to a monovalent group having two or more ringscondensed (fused) to each other, at least one heteroatom selected fromN, O, Si, P, and S as a ring-forming atom, and carbon atoms as theremaining ring-forming atoms (e.g., having 1 to 60 carbon atoms), and nooverall aromaticity in its entire molecular structure. A non-limitingexample of the monovalent non-aromatic condensed heteropolycyclic groupis a carbazolyl group. The term “divalent non-aromatic condensedheteropolycyclic group” as used herein may refer to a divalent grouphaving the same structure as the monovalent non-aromatic condensedheteropolycyclic group.

The term “C₅-C₆₀ carbocyclic group” as used herein may refer to amonocyclic or polycyclic group having 5 to 60 carbon atoms in which aring-forming atoms are carbon atoms only. The C₅-C₆₀ carbocyclic groupmay be an aromatic carbocyclic group or a non-aromatic carbocyclicgroup. The C₅-C₆₀ carbocyclic group may be a ring (such as benzene), amonovalent group (such as a phenyl group), or a divalent group (such asa phenylene group). In one or more embodiments, depending on the numberof substituents connected to the C₅-C₆₀ carbocyclic group, the C₅-C₆₀carbocyclic group may be a trivalent group or a quadrivalent group.

The term “C₁-C₆₀ heterocyclic group” as used herein may refer to a grouphaving the same structure as a C₁-C₆₀ carbocyclic group, except that asa ring-forming atom, at least one heteroatom selected from N, O, Si, P,and S is used, in addition to carbon atoms (e.g., the number of carbonatoms may be in a range of 1 to 60).

At least one substituent of the substituted C₅-C₆₀ carbocyclic group,the substituted C₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group,the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, thesubstituted C₁-C₆₀ heteroarylene group, the substituted divalentnon-aromatic condensed polycyclic group, the substituted divalentnon-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀ alkenyl group, the substitutedC₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, thesubstituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group may be selectedfrom:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently beselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.

The term “Ph” as used herein may refer to a phenyl group, the term “Me”as used herein may refer to a methyl group, the term “Et” as used hereinmay refer to an ethyl group, the term “ter-Bu” or “Bu^(t),” as usedherein, may refer to a tert-butyl group, the term “OMe” as used hereinmay refer to a methoxy group, and “D” as used herein may refer todeuterium.

The term “biphenyl group” as used herein may refer to a “phenyl groupsubstituted with a phenyl group. For example, the “biphenyl group” maybe referred to as a “substituted phenyl group” having a “C₆-C₆₀ arylgroup” as a substituent.

The term “terphenyl group” as used herein may refer to a “phenyl groupsubstituted with a biphenyl group. For example, the “terphenyl group”may be referred to as a “phenyl group” having, as a substituent, a“C₆-C₆₀ aryl group substituted with a C₆-C₆₀ aryl group.”

*and *′ as used herein, unless defined otherwise, each refers to abinding site to a neighboring atom in a corresponding formula.

Hereinafter, a compound according to one or more embodiments of thepresent disclosure, and an organic light-emitting device including thecompound, will be described in more detail with reference to SynthesisExamples and Examples. The expression “B was used instead of A” used indescribing Synthesis Examples and Examples may refer to an identicalnumber of molar equivalents of A being used in place of molarequivalents of B.

SYNTHESIS EXAMPLES Synthesis Example 1 Synthesis of Compound 1

1) Synthesis of Intermediate 1-1

9,9-dimethyl-9,10-dihydroacridine (CAS #6267-02-3) was reacted withnBuLi, and then reacted with dichlorophenylphosphine, to obtainIntermediate 1-1. Intermediate 1-1 was identified by liquidchromatography-mass spectrometry (LC-MS). C₃₆H₃₃N₂P: M+1 525.4.

2) Synthesis of Compound 1

3.2 g of Intermediate 1-1 was dissolved in 30 mL of methylene chloride(MC), and 10 mL of peroxide was added thereto dropwise. Then, theresultant mixture was stirred at room temperature for 2 hours. Theobtained reaction mixture was extracted by using MC. Then, an organiclayer collected therefrom was dried by using magnesium sulfate, and asolvent was evaporated therefrom. Then, a residue obtained therefrom wasseparated and purified by silica gel column chromatography to obtain 2.6g (yield: 79%) of Compound 1. Compound 1 was identified by LC-MS and¹H-NMR.

Synthesis Example 2 Synthesis of Compound 2

Synthesis of Intermediate 2-1

9,9-diphenyl-9,10-dihydroacridine (CAS #20474-15-1) was reacted withnBuLi, and then reacted with dichlorophenylphosphine, to obtainIntermediate 2-1. Intermediate 2-1 was identified by LC-MS.

C₅₆H₄₁N₂P: M+1 773.4.

Synthesis of Compound 2

2.6 g of Intermediate 2-1 was dissolved in 30 mL of MC, and 10 mL ofperoxide was added thereto dropwise. Then, the resultant mixture wasstirred at room temperature for 2 hours. The obtained reaction mixturewas extracted by using MC. Then, an organic layer collected therefromwas dried by using magnesium sulfate, and a solvent was evaporatedtherefrom. Then, a residue obtained therefrom was separated and purifiedby silica gel column chromatography to obtain 2.2 g (yield: 81%) ofCompound 2. Compound 2 was identified by LC-MS and ¹H -NMR.

Synthesis Example 3 Synthesis of Compound 3

Synthesis of Intermediate 3-1

10,10-diphenyl-5,10-dihydrobenzo [b,e][1,4]azaciline (CAS #3508-62-1)was reacted with nBuLi, and then reacted with dichlorophenylphosphine,to obtain Intermediate 3-1. Intermediate 3-1 was identified by LC-MS.

C₅₄H₄₁N₂PSi₂: M+1 805.1.

Synthesis of Compound 3

1.9 g of Intermediate 3-1 was dissolved in 30 mL of MC, and 10 mL ofperoxide was added thereto dropwise. Then, the resultant mixture wasstirred at room temperature for 2 hours. The obtained reaction mixturewas extracted by using MC. Then, an organic layer collected therefromwas dried by using magnesium sulfate, and a solvent was evaporatedtherefrom. Then, a residue obtained therefrom was separated and purifiedby silica gel column chromatography to obtain 1.4 g (yield: 69%) ofCompound 3. Compound 3 was identified by LC-MS and ¹H -NMR.

Synthesis Example 4 Synthesis of Compound 7

Synthesis of Intermediate 7-1

3-bromopyridine was reacted with isopropylmagnesium chloride, and thenreacted with dichlorophenylphosphine, to obtainphenyl(pyridine-3-yl)phosphinic chloride (Intermediate A).10-(9H-carbazole-3-yl)-9,9-dimethyl-9,10-dihydroacridine (CAS#1821228-18-5) was reacted with nBuLi to obtain lithium3-(9,9-dimethylacridine-10(9H)-yl)carbazolide (Intermediate B).Intermediate A was reacted with Intermediate B to obtain Intermediate7-1. Intermediate 7-1 was identified by LC-MS.

C₃₈H₃₀N₃P : M+1 560.7.

Synthesis of Compound 7

3.3 g of Intermediate 7-1 was dissolved in 30 mL of MC, and 10 mL ofperoxide was added thereto dropwise. Then, the resultant mixture wasstirred at room temperature for 2 hours. The obtained reaction mixturewas extracted by using MC.

Then, an organic layer collected therefrom was dried by using magnesiumsulfate, and a solvent was evaporated therefrom. Then, a residueobtained therefrom was separated and purified by silica gel columnchromatography to obtain 2.2 g (yield: 66%) of Compound 7. Compound 7was identified by LC-MS and ¹H -NMR.

Synthesis Example 5 Synthesis of Compound 8

Synthesis of Intermediate 8-1

10-(9H-carbazole-3-yl)-9,9-dimethyl-9,10-dihydroacridine (CAS#1821228-18-5) was reacted with nBuLi, and then reacted withdichlorophenylphosphine, to obtain Intermediate 8-1. Intermediate 8-1was identified by LC-MS.

C₃₉H₃₁N₂P: M+1 559.3.

Synthesis of Compound 8

2.9 g of Intermediate 8-1 was dissolved in 30 mL of MC, and 10 mL ofperoxide was added thereto dropwise. Then, the resultant mixture wasstirred at room temperature for 2 hours. The obtained reaction mixturewas extracted by using MC. Then, an organic layer collected therefromwas dried by using magnesium sulfate, and a solvent was evaporatedtherefrom. Then, a residue obtained therefrom was separated and purifiedby silica gel column chromatography to obtain 2.6 g (yield: 87%) ofCompound 8. Compound 8 was identified by LC-MS and ¹H -NMR.

Synthesis Example 6 Synthesis of Compound 11

Synthesis of Intermediate 11-1

9H-3,9′-bicarbazole (CAS #18628-07-4) was reacted with nBuLi, and thenreacted with dichlorophenylphosphine, to obtain Intermediate 11-1.Intermediate 11-1 was identified by LC-MS.

C₃₆H₂₅N₂P: M+1 517.33.

Synthesis of Compound 11

3.6 g of Intermediate 11-1 was dissolved in 30 mL of MC, and 10 mL ofperoxide was added thereto dropwise. Then, the resultant mixture wasstirred at room temperature for 2 hours. Then, the obtained reactionmixture was extracted by using MC. Then, an organic layer collectedtherefrom was dried by using magnesium sulfate, and a solvent wasevaporated therefrom. Then, a residue obtained therefrom was separatedand purified by silica gel column chromatography to obtain 3.1 g (yield:83%) of Compound 11. Compound 11 was identified by LC-MS and ¹H -NMR.

Synthesis Example 7 Synthesis of Compound 27

Synthesis of Compound 27

2.7 g of Intermediate 3-1 was dissolved in 30 mL of MC, and then reactedwith dichlorophenylphosphine. Then, 0.3 g of sulfur was added theretodropwise. Then, the resultant mixture was stirred at room temperaturefor 2 hours. Then, the obtained reaction mixture was extracted by usingMC. Then, an organic layer collected therefrom was dried by usingmagnesium sulfate, and a solvent was evaporated therefrom. Then, aresidue obtained therefrom was separated and purified by silica gelcolumn chromatography to obtain 2.2 g (yield: 76%) of Compound 27.Compound 27 was identified by LC-MS and ¹H -NMR.

¹H NMR and MS/FAB results of compounds synthesized in Synthesis Examples1 to 8 are shown in Table 1 below.

Synthesis methods of compounds other than the compounds shown in Table 1below should become apparent those of ordinary skill in the art byreferring to the synthesis mechanisms and source materials describedabove.

TABLE 1 MS/FAB Found Compound ¹H NMR (CDCl₃, 400 MHz) [M + 1] calc. 17.31 (d, 2H), 7.27-7.23 (m, 3H), 541.33 540.23 7.18-7.14 (m, 12H), 6.92(t, 4H), 1.65 (s, 12H) 2 7.33 (d, 2H), 7.28-7.22 (m, 19H), 789.33 788.307.19-7.13 (m, 16H), 7.11 (d, 8H), 6.92 (t, 4H) 3 7.47 (d, 8H), 7.41-7.36(m, 20H), 821.27 820.25 7.30-7.20 (m, 9H), 7.03 (t, 4H) 7 9.13 (s, 1H),8.77 (d, 1H), 8.55 576.44 575.21 (d, 11H), 8.26 (d, 1H), 7.93 (d, 1H),7.76 (d, 2H), 7.55-7.51 (m, 5H), 7.36-7.32 (m, 3H), 7.20-7.13 (m, 7H),6.99 (t, 2H), 1.69 (s, 6H) 8 8.54 (d, 1H), 7.93 (d, 1H), 7.76 575.11574.22 (d, 4H), 7.52 (d, 1H), 7.36-7.31 (m, 3H), 7.17-7.12 (m, 7H), 6.94(t, 2H), 1.67 (s, 6H) 11 8.56-8.54 (m, 2H), 8.20 (d, 1H), 533.21 532.177.95 (d, 1H), 7.78-7.70 (m, 5H), 7.67 (s, 1H), 7.57 (d, 1H), 7.52- 7.48(m, 7H), 7.39-7.32 (m, 3H), 7.2-7.15 (m, 3H) 27 7.47-7.40 (m, 12H),7.37-7.32 (m, 837.41 836.23 16H), 7.29-7.25 (m, 3H), 7.01 (t, 4H)

EXAMPLES Example 1

As an anode, a Corning 15 Ω/cm² (500 Å) ITO glass substrate was cut to asize of 50 mm×50 mm×0.5 mm, sonicated with isopropyl alcohol and purewater, for 10 minutes in each, and then cleaned by exposure toultraviolet rays and ozone for 10 minutes. Then, the resultant ITO glasssubstrate was placed in a vacuum deposition apparatus.

NPD was vacuum-deposited on the ITO glass substrate to form a holeinjection layer having a thickness of 300 Å, and CzSi wasvacuum-deposited on the hole injection layer to form a hole transportlayer having a thickness of 200 Å.

Compound 1 and Ir(pmp)₃ were co-deposited on the hole transport layer ata weight ratio of 92:8 to form an emission layer having a thickness of250 Å.

Then, TSP01 was vacuum-deposited on the emission layer to form anelectron transport layer having a thickness of 200 Å.

LiF was deposited on the electron transport layer to form an electroninjection layer having a thickness of 10 Å, and Al was vacuum-depositedon the electron injection layer to form a cathode having a thickness of100 Å, thereby completing the manufacture of an organic light-emittingdevice.

Example 2

An organic light-emitting device was manufactured in the same (orsubstantially the same) manner as in Example 1, except that Compound 2was used instead of Compound 1 in forming an emission layer.

Example 3

An organic light-emitting device was manufactured in the same (orsubstantially the same) manner as in Example 1, except that Compound 3was used instead of Compound 1 in forming an emission layer.

Example 4

An organic light-emitting device was manufactured in the same (orsubstantially the same) manner as in Example 1, except that Compound 7was used instead of Compound 1 in forming an emission layer.

Example 5

An organic light-emitting device was manufactured in the same (orsubstantially the same) manner as in Example 1, except that Compound 8was used instead of Compound 1 in forming an emission layer.

Example 6

An organic light-emitting device was manufactured in the same (orsubstantially the same) manner as in Example 1, except that Compound 11was used instead of Compound 1 in forming an emission layer.

Example 7

An organic light-emitting device was manufactured in the same (orsubstantially the same) manner as in Example 1, except that Compound 27was used instead of Compound 1 in forming an emission layer.

Comparative Example 1

An organic light-emitting device was manufactured in the same (orsubstantially the same) manner as in Example 1, except that BCPO wasused instead of Compound 1 in forming an emission layer.

Comparative Examples 2 to 4

Organic light-emitting devices were manufactured in the same (orsubstantially the same) manner as in Example 1, except that Compounds 1to 3 were respectively used instead of Compound 1 in forming an emissionlayer.

Comparative Compound 1

Comparative Compound 2

Comparative Compound 3

Evaluation Example 1

The driving voltage, luminescent efficiency, and color coordinates ofeach of the organic light-emitting devices manufactured according toExamples 1 to 7 and Comparative Examples 1 to 4 were measured by using aKeithley SMU 236 and a luminance meter PR650 at 600 nit. Results thereofare shown in Table 2 below.

TABLE 2 Maximum Driving Current quantum Emis- Emission voltage densityefficiency sion layer (V) (mA/cm²) (%) color Example 1 Compound 1 4.25.5 20.5 blue Example 2 Compound 2 4.3 5.5 19.9 blue Example 3 Compound3 4.4 5.5 18.8 blue Example 4 Compound 7 3.8 5.5 21 blue Example 5Compound 8 3.7 5.5 22.1 blue Example 6 Compound 11 3.8 5.5 19.9 blueExample 7 Compound 27 4.4 5.5 18.9 blue Comparative BCPO 4.9 5.5 14.9blue Example 1 Comparative Comparative 4.7 5.5 4.4 blue Example 2Compound 1 Comparative Comparative 4.9 5.5 14.4 blue Example 3 Compound2 Comparative Comparative 5.5 5.5 13.3 blue Example 4 Compound 3

Referring to Table 2, it can be seen that the organic light-emittingdevices of Examples 1 to 7 exhibited lower driving voltage, as comparedwith the organic light-emitting devices of Comparative Examples 1 to 4.Also, it can be seen that the organic light-emitting devices of Examples1 to 7 exhibited excellent characteristics in terms of luminescentefficiency, as compared with the organic light-emitting devices ofComparative Examples 1 to 4.

Example 8

As an anode, a Corning 15 Ω/cm² (1,200 Å) ITO glass substrate was cut toa size of 50 mm×50 mm×0.7 mm, sonicated with isopropyl alcohol and purewater, for 5 minutes in each, and then cleaned by exposure toultraviolet rays and ozone for 30 minutes. Then, the resultant ITO glasssubstrate was placed in a vacuum deposition apparatus.

α-NPD was vacuum-deposited on the ITO glass substrate to form a holeinjection layer having a thickness of 300 Å, and TCTA as a holetransport compound was vacuum-deposited on the hole injection layer toform a hole transport layer having a thickness of 200 Å. CzSi as a holetransport layer compound was vacuum-deposited on the hole transportlayer to form a layer having a thickness of 100 Å. Compound H101 andCompound 3 were co-deposited on the CzSi layer at a weight ratio of90:10 to form an emission layer having a thickness of 200 Å. Then,Compound H101 as an electron transport layer compound was formed to athickness of 200 Å, and TPBI as an electron injection layer compound wasdeposited to a thickness of 300 Å.

LiF, which is an alkali metal halide, was deposited on the electrontransport layer to form an electron injection layer having a thicknessof 10 Å, and Al was vacuum-deposited to form a cathode electrode havinga thickness of 3,000 Å, thereby forming a LiF/Al electrode. In thismanner, an organic light-emitting device was manufactured.

Examples 9 and 10 and Comparative Example 5

Organic light-emitting devices were manufactured in the same (orsubstantially the same) manner as in Example 8, except that thecompounds shown in Table 3 were respectively used instead of Compound 3in forming an emission layer.

Evaluation Example 2

The driving voltage, luminescent efficiency, and color coordinates ofeach of the organic light-emitting devices manufactured according toExamples 8 to 11 and Comparative Example 5 were measured by using aKeithley SMU 236 and a luminance meter PR650 at 600 nit. Results thereofare shown in Table 3 below.

TABLE 3 Maximum Driving Current quantum Emis- Emission voltage densityefficiency sion layer (V) (mA/cm²) (%) color Example 8 Compound 3 6.4 222.5 blue Example 9 Compound 7 6.2 2 23.9 blue Example 10 Compound 8 6.32 19.3 blue Example 11 Compound 11 6.2 2 22 blue Comparative DPS 7.4 216.7 blue Example 5

Referring to Table 3, it can be seen that the organic light-emittingdevices of Examples 8 to 11 exhibited lower driving voltage, as comparedwith the organic light-emitting device of Comparative Example 5. Also,it can be seen that the organic light-emitting devices of Examples 8 to11 exhibited excellent maximum quantum efficiency, as compared with theorganic light-emitting device of Comparative Example 5.

An organic light-emitting device including the heterocyclic compoundaccording to embodiments of the present disclosure may have a lowdriving voltage, a high efficiency, a high luminance, and a longlifespan.

It should be understood that embodiments described herein should beconsidered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as available for other similar featuresor aspects in other embodiments.

As used herein, the terms “use,” “using,” and “used” may be consideredsynonymous with the terms “utilize,” “utilizing,” and “utilized,”respectively.

In addition, the terms “substantially,” “about,” and similar terms areused as terms of approximation and not as terms of degree, and areintended to account for the inherent deviations in measured orcalculated values that would be recognized by those of ordinary skill inthe art.

Also, any numerical range recited herein is intended to include allsub-ranges of the same numerical precision subsumed within the recitedrange. For example, a range of “1.0 to 10.0” is intended to include allsubranges between (and including) the recited minimum value of 1.0 andthe recited maximum value of 10.0, that is, having a minimum value equalto or greater than 1.0 and a maximum value equal to or less than 10.0,such as, for example, 2.4 to 7.6. Any maximum numerical limitationrecited herein is intended to include all lower numerical limitationssubsumed therein and any minimum numerical limitation recited in thisspecification is intended to include all higher numerical limitationssubsumed therein. Accordingly, Applicant reserves the right to amendthis specification, including the claims, to expressly recite anysub-range subsumed within the ranges expressly recited herein.

It will be understood that when an element is referred to as being “on,”“connected to,” or “coupled to” another element, it may be directly on,connected, or coupled to the other element or one or more interveningelements may also be present. When an element is referred to as being“directly on,” “directly connected to,” or “directly coupled to” anotherelement, there are no intervening elements present. For example, when afirst element is described as being “coupled” or “connected” to a secondelement, the first element may be directly coupled or connected to thesecond element or the first element may be indirectly coupled orconnected to the second element via one or more intervening elements.

While one or more embodiments have been described with reference to thedrawing, it will be understood by those of ordinary skill in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope of the present disclosure as definedby the following claims and equivalents thereof.

What is claimed is:
 1. An organic light-emitting device comprising: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer comprising an emission layer and at least one heterocyclic compound represented by Formula 1, wherein the first electrode is an anode, the second electrode is a cathode, the organic layer further comprises a hole transport region, between the first electrode and the emission layer, and an electron transport region, between the emission layer and the second electrode, the hole transport region comprises at least one layer selected from a hole injection layer, a hole transport layer, a buffer layer, an emission auxiliary layer, and an electron blocking layer, the electron transport region comprises at least one layer selected from a hole blocking layer, an electron transport layer, and an electron injection layer, the heterocyclic compound is in the emission layer and is a delayed fluorescent dopant, the emission layer further comprises a host, and the delayed fluorescent dopant and the host satisfy Equation 2 or Equation 3: |E _(H,HOMO)-E _(D,HOMO)|≤0.5eV  Equation 2 E _(H,LUMO)-E _(D,LUMO)|≤0.5 eV,  Equation 3 wherein, in Equations 2 and 3, E_(H, HOMO) is a highest occupied molecular orbital level of the host, E_(D, HOMO) is a highest occupied molecular orbital level of the dopant, E_(H, LUMO) is a lowest unoccupied molecular orbital level of the host, and E_(D, LUMO) is a lowest unoccupied molecular orbital level of the dopant:

wherein, in Formulae 1, 2-1, 2-2, 3-1, and 3-2, X₁ is O or S, Ar₁ and Ar₂ are each independently a substituted or unsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₂-C₆₀ heterocyclic group, a1 and a2 are each independently an integer from 0 to 3, b1 and b2 are each independently 0 or 1, a1, a2, b1, and b2 satisfy a1+b1≥1 and a2+b2≥1, R₁ and R₂ are each independently a group represented by Formula 2-1, R₃ is a group represented by Formula 2-2, A₁ to A₄ are each independently selected from a benzene group, a naphthalene group, a phenanthrene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, and a tetrazine group, A₅ to A₈ are each independently selected from a benzene group, a naphthalene group, a phenanthrene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, and a tetrazine group, Y₁ is a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉), Y₂ is a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉), Y₃ is a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉), Y₄ is a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉), Y₅ is a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), Si(R₁₉)(R₂₀), S(═O)(R₁₉), S(═O)₂(R₁₉), or P(═O)(R₁₉), wherein (i) when Y₂ is a single bond, S, or O, a group represented by Formula 2-1 and a group represented by Formula 2-2 are different from each other, and (ii) when -(Ar₁)_(a1)-(R₁)_(b1) and -(Ar₂)_(a2)-(R₂)_(b2) each represent a phenyl group, either Y₂ is S(═O)(R₁₉) or S(═O)₂(R₁₉), or at least one of R₁₃ and R₁₄ is selected from a group represented by Formula 3-1 and a group represented by Formula 3-2, R₁₁ to R₁₄ are each independently selected from a group represented by Formula 3-1, a group represented by Formula 3-2, hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —S(═O)(Q₁), and —P(═O)(Q₁)(Q₂), wherein two or more R₁₁(s) are optionally linked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₂-C₆₀ heterocyclic group, two or more R₁₂(s) are optionally linked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₂-C₆₀ heterocyclic group, two or more R₁₃(s) are optionally linked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₂-C₆₀ heterocyclic group, and two or more R₁₄(s) are optionally linked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₂-C₆₀ heterocyclic group, b11 to b14 are each independently an integer from 1 to 8, when X₁ is O, at least one of R₁₃ and R₁₄ is a group represented by Formula 3-1 or a group represented by Formula 3-2, provided that Y₂ and Y₃ are not both a single bond at the same time, and Y₂ and Y₄ or Y₂ and Y₅ are not both a single bond at the same time, R₁₅ to R₂₀ are each independently selected from hydrogen, deuterium, —F, —Cl , —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic, —S(═O)(Q₁), and —P(═O)(Q₁)(Q₂), b15 to b18 are each independently an integer from 1 to 8, at least one substituent of the substituted C₅-C₆₀ carbocyclic group, the substituted C₂-C₆₀ heterocyclic group, the substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group is selected from: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, -Si(Q₁₁)(Q₁₂)(Q₁₃), -N(Q₁₁)(Q₁₂), -B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, -Si(Q₂₁)(Q₂₂)(Q₂₃), -N(Q₂₁)(Q₂₂), -B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and -Si(Q₃₁)(Q₃₂)(Q₃₃), -N(Q₃₁)(Q₃₂), -B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), Q₁, Q₂, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ are each independently selected from hydrogen, deuterium, —F, -C₁, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group, and *indicates a binding site to a neighboring atom.
 2. The organic light-emitting device of claim 1, wherein a1, a2, b1, and b2 satisfy a1+b1=1 and a2+b2=1.
 3. The organic light-emitting device of claim 1, wherein b1 and b2 satisfy b1+b2=0 or b1+b2=1.
 4. The organic light-emitting device of claim 1, wherein, when Y₂ is O, Y₁ is a single bond, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), or Si(R₁₉)(R₂₀).
 5. The organic light-emitting device of claim 1, wherein Ar₁ and Ar₂ are each independently a substituted or unsubstituted aromatic C₆-C₃₀ carbocyclic group or a substituted or unsubstituted π electron-depleted nitrogen-containing C₂-C₃₀ heterocyclic group.
 6. The organic light-emitting device of claim 1, wherein A₁ to A₄ are each independently a benzene group, a pyridine group, or a pyrimidine group, and A₅ to A₈ are each independently a benzene group, a pyridine group, or a pyrimidine group.
 7. The organic light-emitting device of claim 1, wherein Y₁ is a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), or Si(R₁₉)(R₂₀), Y₂ is a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), or Si(R₁₉)(R₂₀), and Y₃ is a single bond, O, S, SO₂, N(R₁₉), C(R₁₉)(R₂₀), or Si(R₁₉)(R₂₀), provided that Y₂ and Y₃ are not both a single bond at the same time.
 8. The organic light-emitting device of claim 1, wherein the heterocyclic compound represented by Formula 1 is represented by Formula 1-1 or Formula 1-2:

wherein, in Formulae 1-1 and 1-2, descriptions of A₁₁, A₁₂, A₂₁, A₂₂, A₃₁, and A₃₂ are each independently the same as the one provided in connection with A₁ to A₄ in Formula 1, descriptions of Y₁₁ and Y₁₃ are each independently the same as the one provided in connection with Y₁ in Formula 1, wherein when -Ar₁ and Ar₂ are each a phenyl group, either Y₁₃ is S(═O)(R₁₉) or S(═O)2(R₁₉), or at least one of R₁₂₁ and R₁₂₂ is selected from a group represented by Formula 3-1 and a group represented by Formula 3-2, description of Y₁₂ is the same as the one provided in connection with Y₂ in Formula 1, when one of Y₁₁ and Y₁₂ is O, the other one of Y₁₁ and Y₁₂ is not O, descriptions of R₁₀₁, R₁₀₂, R₁₁₁, R₁₁₂, R₁₂₁, and R₁₂₂ are each independently the same as the one provided in connection with R₁₁ to R₁₄ in Formula 1, and descriptions of X₁, Ar₁, and Ar₂ are respectively the same as those provided in connection with Formula
 1. 9. The organic light-emitting device of claim 1, wherein R₁₁ to R₁₄ are each independently selected from: a group represented by Formula 3-1, a group represented by Formula 3-2, hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxy group, a phenyl group, an acridyl group, and a carbazolyl group; and a phenyl group, an acridyl group, and a carbazolyl group, each substituted with at least one substituent selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, and a C₁-C₂₀ alkoxy group, wherein when X₁ is 0, at least one of R₁₃ and R₁₄ is a group represented by Formula 3-1 or a group represented by Formula 3-2.
 10. The organic light-emitting device of claim 1, wherein when Y₁ is a single bond, the group represented by Formula 2-1 is a group represented by Formula 2-2-1:

wherein, in Formula 2-2-1, R₂₈ is a group represented by Formula 3-1 or a group represented by Formula 3-2, and descriptions of R₂₁ to R₂₇ are each independently the same as the one provided in connection with R₁₁ to R₁₄ in Formula
 1. 11. The organic light-emitting device of claim 10, wherein R₂₃ is selected from: hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, a phenyl group, a naphthyl group, a fluorenyl group, a pyridinyl group, a pyrimidyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, and a terphenyl group; and a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, a phenyl group, a naphthyl group, a fluorenyl group, a pyridinyl group, a pyrimidyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, and a terphenyl group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, and a terphenyl group, and R₂₁, R₂₂, and R₂₄ to R₂₇ are each hydrogen.
 12. The organic light-emitting device of claim 1, wherein the group represented by Formula 3-1 is represented by Formula 3-1-1:

wherein, in Formula 3-1-1, descriptions of Y₃, R₁₅, and R₁₆ are respectively the same as those provided in connection with Formula 1, and *indicates a binding site to a neighboring atom.
 13. The organic light-emitting device of claim 1, wherein R₁₅ to R₂₀ are each independently selected from: hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a C₁-C₂₀ alkoxy group, and a phenyl group; and a phenyl group substituted with at least one substituent selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, and a C₁-C₂₀ alkoxy group.
 14. The organic light-emitting device of claim 1, wherein the heterocyclic compound satisfies Equation 1: |E _(D,S1)-E _(D,T1)|≤0.3 eV  Equation 1 wherein, in Equation 1, E_(D,S1) is a singlet energy level (eV) of the delayed fluorescent dopant, and E_(D,T1) is a triplet energy level (eV) of the delayed fluorescent dopant.
 15. The organic light-emitting device of claim 1, wherein the host is one of Compounds H101 to H106:


16. An organic light-emitting device comprising: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer comprising an emission layer and at least one heterocyclic compound selected from Compounds 4 to 10, 12 to 17, 19 to 24, and 28 to 30, wherein the first electrode is an anode, the second electrode is a cathode, the organic layer further comprises a hole transport region, between the first electrode and the emission layer, and an electron transport region, between the emission layer and the second electrode, the hole transport region comprises at least one layer selected from a hole injection layer, a hole transport layer, a buffer layer, an emission auxiliary layer, and an electron blocking layer, the electron transport region comprises at least one layer selected from a hole blocking layer, an electron transport layer, and an electron injection layer, wherein the heterocyclic compound is in the emission layer and is a delayed fluorescent dopant, the emission layer further comprises a host, and the delayed fluorescent dopant and the host satisfy Equation 2 or Equation 3: |E _(H,HOMO)-E _(D,HOMO) |≤0.5 eV  Equation 2 |E _(H,LUMO)-E _(D,LUMO) |≤0.5 eV  Equation 3 wherein, in Equations 2 and 3, E_(H, HOMO) is a highest occupied molecular orbital level of the host, E_(D, HOMO) is a highest occupied molecular orbital level of the dopant, E_(H, LUMO) is a lowest unoccupied molecular orbital level of the host, and E_(D, LUMO) is a lowest unoccupied molecular orbital level of the dopant:


17. A heterocyclic compound selected from Compounds 5 to 10, 12 to 17, 19 to 24, 29, and 30: 